Two hundreads patients who underwent hepatic multiphase CT using LCIC and 189 patients who underwent hepatic multiphase CT using HCIC were included after exclusion criteria applied. The iodine amount that was administered to each patient was also recorded. A margin of -0.5 for the difference between the two CT was pre-defined as noninferiority of the overall image quality of the arterial phase image. Qualitative and quantitative image quality and diagnostic performance were also compared. The cut-off value for the amount of iodine per kg that showed an overall image quality of 5 on arterial phase was evaluated using Area under the curve (AUC) analysis.